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Assembly design - Over Constrained / Inconsistent Error

Assembly design - Over Constrained / Inconsistent Error

Assembly design - Over Constrained / Inconsistent Error

(OP)
Hello,

Simple Question (I hope)

In assembly design, I keep getting the error: "Ignored constraint: the system of constraints is inconsistent or over-constrained"

I KNOW it's not over-constrained cause there are DOFs.  What I have is basically a 4 sided rectangular frame.  I have 3 sides in the assembly.  I make 3 individual surfaces coinciendent, such that they are now all in the same plane.  I then create a distance mate between the two parallel sides.  This is when the error pops up.  

Any ideas?  

I hope this was a clear description.

What I have been able to do to avoid this is to move component by snapping and then "fix" the two parts together.

RE: Assembly design - Over Constrained / Inconsistent Error

I had the same problem in the past. I deleted all constraints and then I added only one align. After regenaration, the same message: "the system of constraints is inconsistent or over-constrained" you are talking.

Solution: Close CATIA and load it back. Problem solved.

Try iy.

-Hora

RE: Assembly design - Over Constrained / Inconsistent Error

I had a similiar problem recently. After doing alot of checking I found out I had a slight angle on one part that was causing two mating parts to not be parallel to each other.  If they are not parallel, then an offset constraint will cause the inconsistancy.

One workaround is apply the offset constraint between a point on each part, instead of a face. This will avoid having the two faces parallel to each other, at least until you have some time to figure out where the problem is.

RE: Assembly design - Over Constrained / Inconsistent Error

CPosner - pay attention to your fixed constraints.  If you apply that constraint (fix) to many items + distance constraints - you will end up over constrained.

Derek

RE: Assembly design - Over Constrained / Inconsistent Error

(OP)
Thanks Everyone.  The parts ended up being something like .009 degrees out of parallel.  I made a parallel constraint and then the other constraints were allowed without the errors.  Thanks!!

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